System and method for germicidal sanitizing of an elevator or other enclosed structure

ABSTRACT

A system for sanitizing an enclosed structure has first and second sensors, a germicidal ultraviolet light source, a motor, and a controller. The first sensor detects humans within the enclosed structure. The second sensor detects the position of at least one door to the structure. The motor selectively moves the light source from an inactive position to an active position. The controller receives inputs from the first and second sensors and transmits outputs to the light source and the motor. When the controller receives signals that no humans or animals are present in the enclosed structure and that the door is in a closed position, the controller transmits a signal to the motor to move the light source from the inactive to the active position. If humans are detected in the structure or if the door is detected open, then the controller deactivates or repositions the light source.

RELATED APPLICATIONS

The present application claims priority benefit, with regard to allcommon subject matter, of earlier-filed U.S. patent application Ser. No.12/754,220, filed Apr. 5, 2010, now U.S. Pat. No. 8,097,861, issued Jan.17, 2012, and entitled “SYSTEM AND METHOD FOR GERMICIDAL SANITIZING OFAN ELEVATOR OR OTHER ENCLOSED STRUCTURE,” which is a continuation ofU.S. patent application Ser. No. 12/186,892, filed Aug. 6, 2008, nowU.S. Pat. No. 7,692,172, issued Apr. 6, 2010, and entitled “SYSTEM ANDMETHOD FOR GERMICIDAL SANITIZING OF AN ELEVATOR OR OTHER ENCLOSEDSTRUCTURE.” The identified earlier-filed patents are hereby incorporatedby reference in their entirety into the present application.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to systems and methods for sanitizingelevators or other enclosed structures. More particularly, the inventionrelates to a system and method for germicidal sanitizing of an elevatoror other enclosed structure using UV light.

2. Description of the Related Art

Environments where humans and animals gather on a frequent basis, suchas schools, medical facilities, and government buildings, may becomebreeding grounds for a variety of harmful microorganisms, such asbacteria, viruses, fungi, and mold. These harmful microorganisms canresult in sickness, infections, disease, and even death. Thesemicroorganisms generally grow on surfaces, such as floors and walls, andinside humans and animals, but may also become airborne to causeinfection, particularly in a confined space such as an elevator.

Traditional approaches to disinfecting an enclosed structure, such as anelevator, have included the use of liquids and gases. Disinfectingliquids usually include bleach or stronger chemicals, which may have adetrimental, or, at the very least, discoloring effect on the surfacesor materials to which the liquids are applied. In addition, liquids maynot be safely applied to electronics or other devices that receiveelectrical power. Furthermore, liquids may not be applied to substancesor materials that are absorbent or are fragile in nature, such as paper.It is also possible that topical liquid antiseptics may induceantibiotic resistance to the very microorganisms they are trying toeradicate. Disinfecting or fumigating gases may include harsh chemicals,such as formaldehyde, which are toxic to humans and animals. Therefore,higher life forms have to be safely removed from the areas wherefumigating gases are being used. Additionally, a great amount of time isrequired for the toxic gas to dissipate from the area once thefumigating is complete. This amount of time may be many hours or evendays. Therefore, neither of these approaches is desirable as theyintroduce toxic agents, require a lot of time, and, of greatest concern,may lead to antibiotic resistance.

SUMMARY OF THE INVENTION

Embodiments of the present invention solve the above-mentioned problemsand provide a distinct advance in the art of sanitizing elevators orother enclosed structures. More particularly, embodiments of theinvention provide a system and method for germicidal sanitizing of anelevator or other enclosed structure using UV light while preventingunintentional exposure to humans or animals.

Embodiments of the sanitizing system of the present invention comprise afirst sensor, a second sensor, a third sensor, an ultraviolet lightsource, a motor, and a controller. The first sensor is operable todetect the absence of humans within the enclosed structure and totransmit a first input signal when humans are absent. The second sensoris operable to detect the position of at least one door of the enclosedstructure and to transmit a second input signal when the door is closed.The third sensor is operable to detect tampering with the system. Theultraviolet light source is operable to provide electromagneticradiation in the ultraviolet range and to receive a first output signalto activate positioning of the ultraviolet light source. The motor isoperable to move the ultraviolet light source and to receive a secondoutput signal to move the ultraviolet light source from an inactiveposition to an active position. The controller is operable to receivethe first input signal and the second input signal, and to transmit thefirst output signal and the second output signal, wherein the controllertransmits the first output signal and the second output signal when thecontroller receives the first input signal and the second input signal.

Embodiments of the method of steps for sanitizing an enclosed structureperformed by the sanitizing system comprise detecting the position of atleast one door in the enclosed structure and detecting the absence ofhumans in the enclosed structure. The method also includes positioningan ultraviolet radiation source within the enclosed structure andactivating the ultraviolet radiation source for a predetermined periodof time when the door is detected to be in a closed position and humansare detected to be absent. The method further includes deactivating theultraviolet light source when the door is detected to be in an openposition, deactivating the ultraviolet light source when humans aredetected to be present, and deactivating the ultraviolet light sourcewhen the predetermined period of time has elapsed. The system can alsobe deactivated if it has been tampered with, such as a person tamperingwith the UV light source.

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the detaileddescription. This summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter.

Other aspects and advantages of the present invention will be apparentfrom the following detailed description of the embodiments and theaccompanying drawing figures.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

Embodiments of the present invention is described in detail below withreference to the attached drawing figures, wherein:

FIG. 1 is a perspective view of a sanitizing system constructed inaccordance with various embodiments of the current invention, depictingthe cutaway of an elevator;

FIG. 2 is an enlarged perspective view of a portion of the sanitizingsystem;

FIG. 3 is a side plan view of a portion of the sanitizing system;

FIG. 4 is a front plan view of a portion of the sanitizing system with asectional view of a protective cover;

FIG. 5 is a lower perspective view of a portion of a second embodimentof the sanitizing system with a sectional view of the protective cover,depicting an ultraviolet light source in an inactive position;

FIG. 6 is an upper perspective view of a portion of the secondembodiment of the sanitizing system, depicting the ultraviolet lightsource in the inactive position;

FIG. 7 is a lower perspective view of a portion of the second embodimentof the sanitizing system with a sectional view of the protective cover,depicting the ultraviolet light source in the active position;

FIG. 8 is an upper perspective view of a portion of the secondembodiment of the sanitizing system, depicting the ultraviolet lightsource in the active position;

FIG. 9 is a lower perspective view of a portion of embodiments of thesanitizing system, depicting a sectional view of the protective coverand the ultraviolet light source rotated approximately 180° from theinactive position;

FIG. 10 is an upper perspective view of a portion of embodiments of thethe sanitizing system, depicting the ultraviolet light source rotatedapproximately 180° from the inactive position;

FIG. 11 is a block diagram of the sanitizing system; and

FIG. 12 is a flow diagram of some of the steps that may be performed bythe sanitizing system.

The drawing figures do not limit the present invention to the specificembodiments disclosed and described herein. The drawings are notnecessarily to scale, emphasis instead being placed upon clearlyillustrating the principles of the invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The following detailed description of the invention references theaccompanying drawings that illustrate specific embodiments in which theinvention can be practiced. The embodiments are intended to describeaspects of the invention in sufficient detail to enable those skilled inthe art to practice the invention. Other embodiments can be utilized andchanges can be made without departing from the scope of the presentinvention. The following detailed description is, therefore, not to betaken in a limiting sense. The scope of the present invention is definedonly by the appended claims, along with the full scope of equivalents towhich such claims are entitled.

Turning now to the drawing figures, and particularly FIG. 1, asanitizing system 10 constructed in accordance with embodiments of theinvention is illustrated. The sanitizing system 10 is operable tosanitize or otherwise clean an elevator 12 or other enclosed structure.Although the sanitizing system 10 of the present invention can be usedin any enclosed structure where bacteria, viruses, mold, germs, fungi,and other similar microorganisms reside, the detailed descriptionprovided below will be with respect to an elevator 12. The sanitizingsystem 10 of embodiments of the present invention comprises a germicidalultraviolet (“UV”) light source 14 (hereinafter “UV light source”), afirst mounting platform 16 on which is mounted the UV light source 14, amotor 18 for rotating or positioning the UV light source 14 in an activeposition, a first sensor 20 for sensing the presence of a human oranimal within the elevator 12, a second sensor 22 for sensing theposition of the elevator's doors 24, a third sensor 25 for sensingtampering of the system 10, and a controller 26 for controllingoperation of the UV light source 14, including the on/off status (ifimplemented) and the position of the UV light source 14. The system 10may also comprise a visible light source 28, a second mounting platform30 on which the visible light source 28 is mounted, and a protectivecover 32.

The UV light source 14 generally serves to provide a source ofdisinfecting radiation in the ultraviolet electro-magnetic (“EM”)radiation range. The UV range is generally considered to be EM radiationof a wavelength between approximately 100 nanometers (“nm”) andapproximately 400 nm. Peak effectiveness for UV radiation as a germicideor disinfectant is between wavelengths of approximately 240 nm andapproximately 280 nm. UV radiation between these wavelengths may destroyDNA in living microorganisms and break down organic material found inthe air in an indoor environment. The wavelength of the UV light source14 is generally fixed when the source is manufactured, although in someembodiments, the wavelength of the UV light source 14 may be variedafter installation, or during operation.

The UV light source 14 may include one or more components operable toemit EM radiation in the UV range, such as lasers, electric arc lamps,pressurized mercury bulbs, or the like. Typically, the UV light source14 includes one or more tube-shaped bulbs 34 with electricallyconductive pins at either one or both ends, such that the UV lightsource 14 may be plugged into a first electrical socket 36. Anelectrical voltage is applied to the pins such that the UV light source14 may be switched on and off like a conventional lamp. The UV lightsource 14 may also include electrical or electronic components thatadjust and maintain the voltage or other electrical properties for theUV light source 14. Operation of the UV light source 14 may becontrolled by the controller 26, such that the controller 26 sends asingle-bit or a simple encoded signal to the UV light source 14. The UVlight source 14 may also send a signal to the controller 26 regardingits status, for example, whether the UV light source 14 is on or off. Inpreferred operation, the UV light source 14 is powered on at all times,as this reduces the wear on the light source 14 and increases thelifespan of the light source 14. Additionally, when the UV light sourceis positioned in an inactive position, as described in more detailbelow, the light source 14 acts as a sanitizer to aerosol in the air.However, if the UV light source 14 is powered on/off, the controller 26is operable to control powering on/off of the UV light source 14.Typically, the controller 26 communicates with the UV light source 14through one or more wires and/or electrically conductive cables,although wireless or other communication methods are possible.

The sanitizing system 10 of embodiments of the present invention isoperable to be mounted in an elevator 12 or other enclosed structure. Asillustrated in FIG. 1, the elevator 12 can be originally manufactured orretrofitted with a drop ceiling 38 that allows room for the UV lightsource 14 to be positioned in an unexposed area when not in use. An“unexposed area,” as used herein, is an area of the elevator 12 or otherenclosed structure that is physically separated from an area of theelevator 12 in which humans will be located, such that a majority of theUV light emitted from the UV light source 14 will not be received by anyhuman in the elevator 12. Therefore, the “exposed area,” as used herein,is the area of the elevator 12 where humans will reside during their useof the elevator 12. The drop ceiling 38 may also include an opening ofsufficient size through which the UV light source 14 may be rotated.

It is advantageous to have the exposed and the unexposed areas in theelevator 12, because UV light can be harmful to a human or animal. Inparticular, UV light can cause eye damage and skin burns after even ashort exposure. Thus, mounting of the UV light source 14 such that itcan be positioned in the unexposed area when not in use provides asafety precaution against a human being accidentally exposed to the UVlight.

The first mounting platform 16 generally retains or holds the UV lightsource 14. Specifically, first electrical sockets 36, into which the UVlight source bulbs 34 are plugged, are attached to the first mountingplatform 16, as seen in FIGS. 3 and 4. The first mounting platform 16may be of a rectangular shape and sufficient size to accommodate one ormore of the UV light source bulbs 34, and may be manufactured frommetals, plastics, wood, or other suitable materials. In embodiments ofthe present invention, the first mounting platform 16 includes areflective surface 37 positioned on the first mounting platform anddirectly behind the UV light source 14. Any UV light incident to thereflective surface 37 is reflected off of the surface 37 and into theelevator 12, thereby increasing the efficiency of the UV light source14. Additionally, a fan 39 may be positioned generally proximate to theUV light source 14 when positioned in the active or inactive position soas to provide air circulation so as to cool the UV light source 14 andprevent it from overheating.

The visible light source 28 generally provides EM radiation ofwavelengths in the visible spectrum (approximately 400 nm toapproximately 700 nm), or as is commonly known, “light.” The visiblelight source 28 may be the sole source of light in the elevator 12 ormay operate in combination with other lights in the elevator 12. Thevisible light source 28 may include any of a variety of visible lightgenerators, such as incandescent bulbs or fluorescent tubes, as arecommonly known. Typically, the visible light source 28 includes one ormore tube-shaped bulbs 42 similar in structure and mass to the UV lightsource bulbs 34 to provide a balanced load to the motor 18, as discussedin more detail below. The visible light source bulbs 42 may also includeone or more electrically conductive pins that may be plugged into asecond electrical socket 44. Likewise with the UV light source 14, anelectrical voltage may be applied to the pins to switch the visiblelight source 28 on and off. The on/off switching of the visible lightsource 28 may be controlled by the controller 26 or may be controlled byanother system for the elevator 12 or the building in which the elevator12 is located.

The second mounting platform 30 generally retains the visible lightsource 28. Particularly, the second electrical sockets 44, into whichthe visible light bulbs 42 are plugged, are attached to the secondmounting platform 30, as seen in FIG. 4. The second mounting platform 30may be of a rectangular shape and sufficient size to accommodate one ormore of the visible light source bulbs 42, and may be manufactured frommetals, plastics, wood, or other suitable materials.

The first mounting platform 16 and the second mounting platform 30 maybe connected to a first bracket 46, which in turn is coupled to anoutput shaft 50 of the motor 18. The first bracket 46 may be generallyU-shaped and include a first leg, a second leg, and a last portion. Thefirst mounting platform 16 is connected to the first leg of the firstbracket 46, and the second mounting platform 30 connected to the secondleg of the first bracket 46, as shown in FIG. 4, such that the firstmounting platform 16 and the second mounting platform 30 are positionedapproximately 180° from each other. A base portion of the first bracket46 is coupled with the output shaft 50 of the motor 18. Thus, as theoutput shaft 50 of the motor 18 rotates, the first bracket 46 and, inturn, the first mounting platform 16 with the UV light source 14 and thesecond mounting platform 30 with the visible light source 28 rotate aswell. In addition, it is generally beneficial if the mass of the firstmounting platform 16 and the UV light source 14 is roughly equivalent tothe mass of the second mounting platform 30 and the visible light source28 in order to provide a balanced load on the shaft of the motor 18 andprovide smooth rotation of the two light sources 14, 28.

The motor 18 may be coupled to a second bracket 48 having an upright legand a horizontal leg. The second bracket, which mounts the motor 18 tothe drop ceiling 38 of the elevator 12, as seen in FIG. 3, near theopening in the drop ceiling 38. The second bracket 48 may also mount themotor 18 to another sturdy fixture of the elevator 12, such as a wall orthe top ceiling of the elevator 12. The second bracket 48 may begenerally L-shaped, such that the body of the motor 18 is coupled to theupright leg of the second bracket 48. The horizontal leg of the secondbracket 48 may be attached to the upper surface of the drop ceiling 38,such that the first bracket 46, the first mounting platform 16, and thesecond mounting platform 30 are positioned so that they can rotatethrough the opening in the drop ceiling 38.

The motor 18 generally rotates the UV light source 14 from an inactiveposition to an active position through the opening in the drop ceiling38, as seen in FIG. 4. The inactive position of the UV light source 14is between the drop ceiling 38 and the top ceiling of the elevator 12,also known as the unexposed area. The active position of the UV lightsource 14 is below the drop ceiling 38, also known as the exposed area,or the main chamber in which people stand while using the elevator 12.Typically, the inactive position is considered to be approximately 90°above the plane of the drop ceiling 38, and the active position isconsidered to be approximately 90° below the plane of the drop ceiling38. The output shaft 50 of the motor 18 may be coupled to the base ofthe first bracket 46, which in turn is attached to the first mountingplatform 16 that holds the UV light source 14. Therefore, rotation ofthe output shaft 50 of the motor 18 approximately 180° in eitherdirection moves the UV light source 14 from the inactive position to theactive position. To return from the active position to the inactiveposition, the output shaft 50 may rotate in the same direction as thefirst rotation, or may rotate in the opposite direction to return theinactive position. As a result, the motor 18 may be capable of rotatingone or more full revolutions in the same direction or roughly halfrevolutions in opposing directions.

The output shaft 50 of the motor 18 may be manufactured from steel orother hardened metals. The motor 18 may include one or more commonlyknown electric motors, such as direct current (“DC”) motors, alternatingcurrent (“AC”) motors, brushless motors, universal motors, steppermotors, servo motors, and the like.

The operation of the motor 18 is generally controlled by the controller26. In various embodiments, the controller 26 may send a single-bit or asimple encoded signal to the motor 18 to adjust the position of the UVlight source 14. Accordingly, the motor 18 may also include electricalor electronic components that translate the controller 26 signal intothe appropriate electrical signal for the motor 18 to rotate and adjustthe position of the UV light source 14. Typically, the controller 26communicates with the motor 18 through one or more wires and/orelectrically conductive cables, although wireless or other communicationmethods are possible.

The protective cover 32 generally prevents tampering or interfering withthe UV light source 14, the visible light source 28, and the motor 18,or any of the other components of the system 10. The protective cover 32may be of any shape that can cover the opening in the drop ceiling 38,while allowing the first mounting platform 16 and the second mountingplatform 30 to rotate freely within the cover. Accordingly, asemi-circular shape may be appropriate with a radius of a circularportion that is at least equal to the length of the longer of either thefirst mounting platform 16 or the second mounting platform 30, as shownin FIG. 4. The protective cover 32 generally attaches to the lowersurface of the drop ceiling 38 around the opening. The protective cover32 may be manufactured from a hardened material, such as certain typesof plastic, metal screen, or quartz, that is transparent or highlytransmissive to UV light in order to allow UV exposure of the interiorof the elevator 12.

The first sensor 20 generally detects the presence of humans or animalsin the elevator 12. The first sensor 20 is usually positioned within theelevator 12 in a location that allows access to the entire volume, or atleast a majority of the volume, of the interior of the elevator 12. Onelocation may be at the bottom of the protective cover 32, such that thefirst sensor 20 faces the doors 24 of the elevator 12, as shown inFIG. 1. The first sensor 20 may be operable to detect any one of orcombinations of a variety of parameters, such as motion, heat, sound,reflected or transmitted light, or the like. The first sensor 20 mayinclude one or more of the following: motion or movement detectors orsensors, thermal or infrared detectors, sensors, or imagers,microphones, sonic or ultrasonic transducers, lasers, light-emittingdiodes (LEDs), photodetectors, photoresistors, and the like.

The first sensor 20 generally transmits a single-bit or simple encodedsignal to the controller 26 to indicate the presence or absence of humanbeings or animals inside the elevator 12 and may include additionalelectronics to generate that signal. The first sensor 20 may communicatewith the controller 26 electrically through one or more wires orelectrically conductive cables, or wirelessly utilizing one or moreradio frequency (“RF”) transmitters and receivers.

The second sensor 22 generally detects the position of the doors 24 ofthe elevator 12. More specifically, the second sensor 22 detects whenthe doors 24 are closed. Thus, the second sensor 22 may be positionedvery close to the elevator doors 24. Typically, the second sensor 22 islocated on the portion of the doors 24 that touches when the doors 24close. The second sensor 22 usually includes a first subsensor 52 and asecond subsensor 54 that work in combination to determine whether theelevator doors 24 are closed. In such an embodiment, the second sensor22 generates a “door closed” signal when the first subsensor 52 is inclose proximity to, or physically touching, the second subsensor 54.Therefore, the first subsensor 52 is located on the mating portion ofone elevator door while the second subsensor 54 is located on the matingportion of the other elevator door in alignment with the first subsensor52, such that when the elevator doors 24 close, the first subsensor 52contacts the second subsensor 54, as seen in FIG. 1. As can beappreciated, if the design of the elevators doors 24 is different, forexample, if one door slides or telescope within another door, then thesecond sensor 22, including the first and second subsensors 52,54, maybe placed in a location different from the location described above.

The first and second subsensors 52, 54 may include simple electricalcontacts that generate a signal or complete an electric circuit whenthey touch. The first and second subsensors 52, 54 may also includepressure or limit switches that activate under mechanical contact,magnetic elements, optical elements, or any combination thereof. Thesecond sensor 22 may also include additional electrical or electroniccomponents that adapt or adjust the signal from the first subsensor 52and the second subsensor 54 that are transmitted to the controller 26.The second sensor 22 may communicate with the controller 26 electricallythrough one or more wires or electrically conductive cables, orwirelessly utilizing one or more RF transmitters and receivers.

The third sensor 25 generally detects any tampering with the system 10of embodiments of the present invention, including without limitationtampering with the UV light source 14, the motor 18, the controller 26,and/or the visible light source 28. The third sensor 20 may bepositioned proximate to the UV light source 14, although multiplesubsensors (not shown) may be positioned at any one of or combination ofthe above UV light source 14, motor 18, controller 26, and visible lightsource 28. The third sensor 25 may include one or more of the following:motion or movement detectors or sensors, thermal or infrared detectors,sensors, or imagers, microphones, sonic or ultrasonic transducers,lasers, light-emitting diodes (LEDs), photodetectors, photoresistors,and the like.

The third sensor 25 generally transmits a single-bit or simple encodedsignal to the controller 26 to indicate movement beyond a pre-definedtolerance or other tampering of the UV light source 14, motor 18,controller 26, and visible light source 28 and may include additionalelectronics to generate that signal. The third sensor 25 may communicatewith the controller 26 electrically through one or more wires orelectrically conductive cables, or wirelessly utilizing one or moreradio frequency (“RF”) transmitters and receivers.

The controller 26 generally receives input data from the first sensor20, the second sensor 22, and the third sensor 25 and transmits controlsignals to the motor 18 and the UV light source 14, as shown in FIG. 11.The conditions that the first sensor 20 and the second sensor 22 monitorlend themselves very well to binary representation. For example, thefirst sensor 20 detects the presence or absence of people in theelevator 12, and the second sensor 22 detects whether the elevator doors24 are opened or closed. Hence, the signals from the first sensor 20 andthe second sensor 22 may be in binary form—a “0” for one condition and a“1” for the other condition. The first sensor 20 and second sensor 22signals may also be in a simple encoded form to provide error detectionand correction capabilities. Likewise, the operation of the motor 18 andpositioning of the UV light source 14 may be implemented with binarysignals. For example, the motor 18 may receive an on/off signal or mayreceive a single pulse signal to instruct the motor 18 to move the UVlight source 14 a predetermined amount. The UV light source 14 may alsoreceive an on/off signal from the controller 26, if desired. Therefore,the signals from the controller 26 to the motor 18 and the UV lightsource 14 may be, for example, a “0” for off and a “1” for on. The motor18 and UV light source 14 signals may also be in a simple encoded formto provide error detection and correction capabilities.

The controller 26 may be implemented in hardware, software, firmware, orcombinations thereof. The controller 26 may include a processing elementcoupled with a memory element that in combination are able to executesoftware code segments that implement the control function. Thecontroller 26 may also include microcomputers, microprocessors,microcontrollers, programmable intelligent computers (PICs),field-programmable gate arrays (FPGAs), programmable logic devices(PLDs), programmable logic controllers (PLCs), and the like. Thecontroller 26 may also be formed or created from one or more codesegments of a hardware description language (HDL). The controller 26 mayalso include a memory component such as hard-disk drives, optical disks,floppy disks, random-access memory (RAM), read-only memory (ROM), cachememory, programmable ROM (PROM), erasable PROM (EPROM), and the like. Inaddition, the controller 26 may include other data input devices such askeyboards, keypads, mice or other pointing devices, knobs, buttons,switches, and the like. The controller 26 may include other data outputdevices such as screens, monitors, displays, speakers, LEDs, liquidcrystal displays (“LCDs”), and the like. Furthermore, the controller 26may include data interfaces, such as a computer network interface, toallow the system 10 to send and receive data from other computers,networks, or systems. Additionally, the controller may be operable witha mainframe controller for the building in which the elevator is housed.

The controller 26 may also include one or more timing elements. Thetiming elements may include count-down timers that wait for apredetermined amount of time, and count-up timers that measure theduration of an event.

The sanitizing system 10 in accordance with various embodiments of thecurrent invention may operate as illustrated in the flow diagram 100 ofFIG. 12. The flow diagram 100 as shown in FIG. 12 provides the generalflow of operation for the system 10; however, certain steps may beperformed concurrently or otherwise out of order from what is shown inFIG. 12. The system 10 operation starts at block 102 in a default state.The controller 26 may checks for tampering at block 104. The controller26 may check the signals it is receiving from the first sensor 20, thesecond sensor 22, and the third sensor 25, or the controller 26 mayreceive feedback from the UV light source 14 or the motor 18. If any ofthese signals are abnormal, the controller 26 may power off and resetthe system 10 as indicated at block 106. Alternatively, the controller26 may perform a self diagnostic check. If any errors are found, thesystem 10 may be reset. After a reset, the system 10 may return to thestart point at block 102.

The controller 26 checks the input from the second sensor 22 todetermine if the elevator doors 24 are closed at block 108. The secondsensor 22 may send a simple binary signal to the controller 26 toindicate yes or no. If the doors 24 are open and the answer is no, thesystem 10 may return to the start point at block 102. If the doors 24are closed and the answer is yes, the controller 26 checks the inputfrom the first sensor 20 to determine if the elevator 12 is occupied atblock 110. The first sensor 20 may send a simple binary signal to thecontroller 26 to indicate yes or no. If the answer is yes and theelevator 12 is occupied, the system 10 may return to the start point atblock 102. If the answer is no and the elevator 12 is unoccupied, thecontroller 26 may prepare to sterilize the elevator 12.

The controller 26 may wait for a safe amount of time, utilizing one ormore timing elements as indicated at block 112. The controller 26 maythen position the UV light source 14 at block 114 from the inactiveposition to the active position. The controller 26 may send an on signalto the motor 18 to rotate the UV light source 14 followed by an offsignal when the UV light is in position. Alternatively, the controller26 may send a pulse signal to the motor 18 to rotate by a predeterminedamount—generally approximately 180°. As noted above, in preferredoperation, the UV light source 14 is powered on at all times, andtherefore, the controller need not instruct the light source 14 to poweron/off in response to positioning of the light source 14. However, ifthe UV light source 14 is powered on/off in response to positioning ofthe light source at block 114, then the controller 26 may turn the UVlight source 14 on at block 116. The controller 26 may send a simplebinary signal to the UV light source 14 to turn it on.

Once the light is positioned in the active position, as illustrated inFIGS. 7 and 8, the controller 26 may start the timing element at block118 to implement a proper sanitizing cycle. The duration that the UVlight source 14 is on, and thus, the duration of the sanitizing cycle,depends on a number of factors including, but not limited to, the sizeof the elevator 12 (particularly the longest dimension of the elevator12), the intensity of the UV output from the UV light source 14, and thetype of microorganism that is targeted. Various microorganisms requiredifferent incident energies, and in turn different exposure times, to bedisabled or have their growth inhibited.

For safety purposes, while the UV light source 14 is in the activeposition, the first sensor 20 and the second sensor 22 still need to bemonitored to prevent accidental exposure to humans or other animals. Thecontroller 26 checks the input from the second sensor 22 to see if theelevator doors 24 are closed at block 120. If the answer is no and thedoors 24 are starting to open, the controller 26 turns the UV lightsource 14 off at block 122. This option of powering off the UV lightsource 14 is preferred due to the possibility of unsafe exposure to ahuman. The controller 26 may send a binary off signal to the UV lightsource 14. The controller 26 repositions the UV light source 14 at block124 from the active position to the inactive position. As describedabove, the controller 26 may send an on signal to the motor 18 to rotatethe UV light source 14 followed by an off signal when the UV light is inposition, or the controller 26 may send a pulse signal to the motor 18to rotate approximately 180°. The controller 26 resets the timingelements at block 126, and the system 10 may return to the start pointat block 102.

If elevator doors 24 are still closed, the controller 26 checks theinput from the first sensor 20 to see if the elevator 12 is occupied atblock 128. While it is not likely that the elevator 12 is occupied atthis point, it may be possible. If the signal from the first sensor 20is yes and the elevator 12 is occupied, then the controller 26 turns theUV light source 14 off at block 122. The system 10 may then follow thesteps discussed above for blocks 124 and 126.

If the elevator doors 24 are closed and the elevator 12 is unoccupied,the controller 26 checks the timer to see if the sanitizing cycle iscomplete. If the timing element has not finished, then the controller 26performs a safety check to see if the doors 24 are closed and theelevator 12 is unoccupied as discussed above at blocks 120 and 128. Ifthe timing element has finished and the sanitizing cycle is complete,the controller 26 repositions the UV light source 14 to the inactiveposition at block 134. Alternatively, if the UV light source 14 is beingpowered on/off dependent on positioning, then the UV light source 14 maybe first powered off at block 132. At this point, the controller mayinstruct the fan 39 to power on so as to provide air circulationproximate to the UV light source 14 so as to cool the UV light source14. The controller 26 stores any relevant data concerning the sanitizingcycle at block 136. The controller 26 may update the sterilizationstatus at block 138 and return to the start point at block 102.

Again and as noted above, when the UV light source 14 is positionedabove the drop ceiling in the inactive position and in the unexposedarea, the UV light source 14 is preferably still turned on, such that itis exposing the air to the UV light, also referred to as aerosol. Thisprovides a system and method of sanitizing the air when the UV lightsource 14 is not in active use in the exposed area of the elevator 12.

A second embodiment for the sanitizing system 10 is shown in FIGS. 5-10.The system 10 may comprise the UV light source 14, the first mountingplatform 16, the motor 18, the first sensor 20, the second sensor 22,the third sensor 25, and the controller 26, all as described above. Thesystem 10 may further comprise a rotatable shelf 56 to which the firstmounting platform 16 is attached, and a linking mechanism 58 thatcouples the shelf 56 to the motor 18. In addition, the system 10 mayinclude a protective cover 32A similar to the one described above.

The shelf 56 may include a front portion 60 and a rear portion 62 with ahinge 64 coupling the front portion 60 to the rear portion 62, andallowing the front portion 60 to rotate about the rear portion 62 whilethe rear portion 62 remains stationary, as seen best in FIGS. 6 and 8.The front portion 60 of the shelf 56 may be elongated so it can receivethe first mounting platform 16. In embodiments of the present inventionand as illustrated in FIG. 7, the rear portion 62 of the shelf 56 mayinclude the reflective surface 37. The surface 37 is preferablypositioned directly behind the UV light source 14. Any UV light incidentto the reflective surface 37 is reflected off of the surface 37 and intothe elevator 12, thereby increasing the efficiency of the UV lightsource 14. Additionally, and as with the first embodiment, the fan 39may be positioned proximate to the UV light source 14 when it ispositioned in the active and inactive position.

In certain embodiments, the front portion 60 of the shelf 56 may beintegrated with or may be the same component as the first mountingplatform 16. The front portion 60 of the shelf 56 may be connected tothe linking mechanism 58. The rear portion 62 of the shelf 56 may beconnected to a third bracket 66.

The third bracket 66 generally couples the shelf 56 to the motor 18, andmay be L-shaped with the shelf 56 connected to the outer surface of oneleg and the motor 18 connected through an opening on the inner surfaceof the other leg, as shown in FIGS. 6, 8, and 10. The motor 18 may becoupled to the upper surface of the drop ceiling 38 at the edge of theopening in the drop ceiling 38. Thus, the shelf 56 with the firstmounting platform 16 and the UV light source 14 attached may bepositioned directly over the opening in the drop ceiling 38.

The linking mechanism 58 couples the front portion 60 of the shelf 56 tothe output shaft 50 of the motor 18. The linking mechanism 58 mayinclude first, second, and third linking components 68, 70, 72 ofvarying lengths that are coupled together end to end. The first linkingcomponent 68 is coupled to the output shaft 50 of the motor 18 and thethird linking component 72 is coupled to the front portion 60 of theshelf 56, such that rotation of the output shaft 50 of the motor 18results in rotation of the front portion 60 of the shelf 56.

The motor 18 generally rotates the UV light source 14 from an inactiveposition to an active position through the opening in the drop ceiling38, as seen in FIGS. 5-10. In the second embodiment, the inactiveposition is where the first mounting platform 16 is approximatelyparallel to the plane of the drop ceiling 38 with the UV light source 14facing generally upward, as illustrated in FIGS. 5 and 6. The activeposition is where the first mounting platform 16 is approximatelyperpendicular to the plane of the drop ceiling 38 with the UV lightsource 14 facing generally outwards, as illustrated in FIGS. 7 and 8. Inmost elevators 12, the system 10 will be positioned within the ceilingof the elevator 12 proximate to a general middle of a back wall of theelevator 12. This location allows for the largest exposure area of theUV light. However, in some instances, it may be desired to placemultiple sanitizing systems 10 within the elevator 12 or other enclosedstructure, especially if a location of only one system 10 will not allowUV light to be exposed to a majority of the surfaces havingmicroorganisms thereon. In this or other instances, it may be desiredfor the UV light source to rotate 180° from the inactive position, asillustrated in FIGS. 9 and 10. As can be appreciated, the UV lightsource 14 may be rotated to any desired angle depending on the desiredexposure area.

The motor 18 of the second embodiment may rotate the output shaft 50 inone direction to move the UV light source 14 from the inactive positionto the active position. However, the motor 18 is generally required torotate the output shaft 50 in the opposite direction to return the UVlight source 14 from the active position to the inactive position. Forexample, if the output shaft 50 rotated in the clockwise direction tomove the UV light source 14 from the inactive position to the activeposition, the output shaft 50 would rotate in the counterclockwisedirection to move the UV light source 14 from the active position to theinactive position. This requirement is due to the structure of the shelf56. Since the rear portion 62 of the shelf 56 is stationary, the frontportion 60 must rotate in the reverse direction to return the UV lightsource 14 to the inactive position. Thus, the motor 18 of the secondembodiment may include additional electrical or electronic circuitry torotate in the appropriate direction when it receives a signal from thecontroller 26 to position the UV light source 14.

The protective cover 32A utilized in the second embodiment, in similarfashion to the embodiments described above, is also attached to thelower surface of the drop ceiling 38 around the perimeter of the openingin the drop ceiling 38, as shown in FIGS. 5, 7, and 9. The protectivecover 32A also has a semi-circular shape, as seen in cutaway in FIGS. 5,7, and 9. However, the cover is elongated to match the length of theaxis of rotation for the front portion 60 of the shelf 56, and in turnthe first mounting platform 16 and the UV light source 14. Thus, theradius of curvature of the protective cover 32A is large enough toaccommodate the motion of the UV light source 14 as it rotates from theinactive position to the active position and back. Likewise, with theprotective cover 32 discussed above, the protective cover 32A isgenerally transparent or highly transmissive to the radiation of the UVlight source 14. Although use of the protective cover 32A is described,in some embodiments of the present invention, the protective cover 32Amay not be used.

The sanitizing system 10 of the second embodiment operates in asubstantially similar fashion as the embodiments described above withregard to the flow diagram of FIG. 12. Although the UV light source 14of the second embodiment is oriented differently from the UV lightsource 14 of the embodiments described above, the performance of thesystem 10 is not substantially affected. The system 10 of the secondembodiment follows the steps of FIG. 12 in substantially the same way asdiscussed above.

The sanitizing system 10 in accordance with various embodiments of thecurrent invention has been disclosed to be utilized with an elevator 12.However, the sanitizing system 10 as disclosed herein may be utilizedwith any confined space or enclosed structure where humans or animalsvisit or congregate but that may be evacuated and sealed off to preventunintentional exposure of UV radiation to the humans or animals during asanitizing cycle. In such implementations, additional sensors may beused to detect the position of additional doors, windows, or otherportals. Examples of confined spaces or enclosed structures include, butare not limited to, hospital rooms, surgical operating rooms, medicalexamining rooms, veterinary offices and operating rooms, hotel rooms,public restrooms, public libraries, school/class rooms, day carecenters, government offices, court rooms, meeting halls, residentialhouses, churches or religious buildings, and the like.

Although the invention has been described with reference to theembodiments illustrated in the attached drawing figures, it is notedthat equivalents may be employed and substitutions made herein withoutdeparting from the scope of the invention as recited in the claims.

1. A sanitizing system for use with an enclosed structure, the systemcomprising: a first sensor to detect the absence or presence of humansor animals within the enclosed structure and to transmit a first inputsignal indicating either the absence or presence of humans or animals; asecond sensor to detect the position of at least one access point of theenclosed structure and to transmit a second input signal indicatingwhether the access point is open or closed; a germicidal ultravioletlight source to provide electromagnetic radiation in the ultravioletrange and to receive a first output signal to activate the ultravioletlight source; and a controller to receive the first input signal and thesecond input signal, and to transmit the first output signal, whereinthe controller transmits the first output signal when the controllerreceives the first input signal indicating the absence of humans oranimals within the enclosed structure and the second input signalindicating that the access point is closed.
 2. The system of claim 1,wherein the controller no longer transmits the first output signal whenthe controller no longer receives the first input signal or the secondinput signal.
 3. The system of claim 1, wherein the first sensorincludes a motion detector.
 4. The system of claim 1, wherein the firstsensor includes a thermal sensor.
 5. The system of claim 1, furtherincluding a third sensor for detecting tampering with the sanitizingsystem.
 6. The system of claim 1, further including a fan mountedproximate the light source for cooling the light source.
 7. The systemof claim 1, wherein the controller is operable to active the lightsource for a predetermined period of time comprising a sanitizing cycle.8. The system of claim 7, wherein a length of time of the sanitizingcycle may be modified based on factors affecting sanitizing of theenclosed structure.
 9. A sanitizing system for use within an enclosedstructure, the system comprising: a first sensor to detect the presenceor absence of humans or animals within the enclosed structure and totransmit a first input signal indicating the presence or absence ofhumans or animals; a second sensor to detect the position of at leastone access point of the enclosed structure and to transmit a secondinput signal indicating whether the access point is open or closed; agermicidal ultraviolet light source to provide electromagnetic radiationin the ultraviolet range and to receive a first output signal toactivate the ultraviolet light source; a selectively movable protectivecover positioned between the light source and the enclosed structure,wherein when the protective cover is in an open position, lightemanating from the light source is transmitted to the enclosedstructure, and further wherein the protective cover is configured to beselectively moved to the open position in response to a second outputsignal; and a controller to receive the first input signal and thesecond input signal, and to transmit the first output signal and thesecond output signal, wherein the controller transmits the first outputsignal and the second output signal when the controller receives thefirst input signal indicating the absence of humans or animals withinthe enclosed structure and the second input signal indicating that theaccess point is closed.
 10. The system of claim 9, further including amounting platform on which the ultraviolet light source is mounted, themounting platform further including a reflective surface for reflectingUV light incident to the surface.
 11. The system of claim 9, wherein thefirst sensor includes a motion detector.
 12. The system of claim 9,wherein the first sensor includes a thermal sensor.
 13. The system ofclaim 9, further including a motor to move the ultraviolet light sourceand to receive a third output signal to move the ultraviolet lightsource from an inactive position to an active position.
 14. Anon-transitory computer-readable medium having a plurality of codesegments stored thereon for instructing a processor to perform thefollowing steps of sanitizing an enclosed structure: a) detecting thepresence or absence of humans or animals in the enclosed structure; b)activating an ultraviolet light source for a predetermined period oftime when humans and animals are detected to be absent from the enclosedstructure; c) if at least one human or animal is detected to be presentin the exposed area, deactivating the ultraviolet light source; and d)deactivating the ultraviolet light source once the predetermined periodof time has elapsed.
 15. The method of claim 14, wherein detecting theabsence of humans or animals in the enclosed structure is accomplishedusing a motion detector.
 16. The method of claim 14, wherein detectingthe absence of humans or animals in the enclosed structure isaccomplished using a thermal sensor.
 17. The method of claim 14, whereina fan is mounted proximate the light source for cooling the lightsource, and further comprising the step of activating the fan for apredetermined period of time after the light source is deactivated. 18.The method of claim 14, wherein the predetermined period of time foractivating the light source may be modified based on factors affectingsanitizing of the enclosed structure.